The use of a cable television (“CATV”) system to provide internet, voice over internet protocol (“VOIP”) telephone, television, and radio services is well known in the art. In providing these services, a downstream bandwidth (i.e., radio frequency (“RF”) signals, digital signals, optical signals, etc.) is passed from a supplier of the services to a user and an upstream bandwidth is passed from the user to the supplier. The downstream bandwidth is passed, for example, within relatively higher frequencies from within a total bandwidth of the CATV system while the upstream bandwidth is passed within relatively lower frequencies.
Traditionally, the size of the downstream bandwidth far exceeds the size of the upstream bandwidth due to nature of the services provided. For example, while the downstream bandwidth must accommodate all of the television and radio programming along with internet and VOIP downloading, the upstream bandwidth is only required to accommodate internet, system control signals, and VOIP uploading. Problems are arising, however, due to an increase in upstream bandwidth usage caused by an increasing demand for higher speed internet uploads and the increasing demand for the VOIP telephone services.
VOIP telephone services places significant demands on the upstream bandwidth. When a user uploads a large image file to a photo sharing website, the image file will be parsed into a number of data packets that can be intermixed with other data packets being passed through a particular portion of the upstream bandwidth by other users located on a particular signal transmission line within the CATV system. To optimize a total data throughput on the particular signal transmission line, the data packets may be significantly delayed and/or reorganized without any knowledge of or inconvenience to the user. When a user uses VOIP telephone services, their voice is converted into data packets that are similar in form to the data packets used to upload the image file. Because a typical conversation is carried out in real time, meaning that a contiguous and unbroken flow of data packets is required, any person with whom the user is talking will quickly notice significant delays in the delivery of the data packets and/or reorganization of the data packets that results in audio distortion of the user's voice. Any such reorganization and/or delay in the uploading of data packets carrying VOIP telephone services are measured in terms of jitter, and are closely monitored because of the significant service quality characteristics it represents.
Jitter experienced between the user and their caller is a direct result of network congestion within the upstream bandwidth. Because the upstream bandwidth is shared by all users on the particular signal transmission line, each user is competing with the other users for packet data space within the upstream bandwidth. Even further, each of the users can unknowingly inject interference signals, such as noise, spurious signals, and other undesirable signals, into the upstream bandwidth through the use of common household items and poor quality wiring in the user's premise, the interference signals causing errors that force a slow down and an additional amount of jitter in the upstream flow of packets.
In an effort to increase the upstream flow of packets, several suppliers have a plan to increase the size of the upstream bandwidth from 5-42 Mhz to 5-85 Mhz to allow a greater flow of the upstream content. Along with such an increase, the downstream bandwidth must be correspondingly decreased in size because the total bandwidth is relatively fixed. Such a change is, however, very difficult to implement.
Traditional practices would require that every drop amplifier and two way (diplex) filter in network amplifiers and nodes of the CATV system to be changed as part of the increasing the size of the upstream bandwidth. Compounding the difficulty of implementing such a change, all of the changes must be implemented at various locations throughout the CATV system at a single, particular time. Accordingly, such an implementation is time consuming, costly, and difficult to coordinate.
Further, while increasing the size of the upstream bandwidth may incrementally increase the flow of upstream data packets, the upstream bandwidth remains susceptible to reliability/congestion issues since it is based on an inherent, system wide flaw that leaves the upstream bandwidth open and easily impacted by any single user. For example, while the downstream bandwidth is constantly monitored and serviced by skilled network engineers, the upstream bandwidth is created and passed using an infrastructure within a user's premise that is maintained by the user without the skill or knowledge required to reduce the creation and passage of interference signals into the upstream bandwidth. This issue is further compounded by the fact that over 500 premises can be connected together such that interference signals generated by one of the 500 premises can easily impact all of the remaining premises. It is common in the art for the supplier to add physical filters between the user's premise and a tap from of the main signal distribution system near the users premise to reduce the impact of the interference signals generated on the user's premise, but such a physical filter must be installed manually and does not account for significant, transient interference sources such as garbage disposals, vacuum cleaners, welders, powered hand tools, etc.
Even further, increasing the size of the upstream bandwidth forces suppliers to push their downstream content into increasingly higher frequency portions of the downstream bandwidth. Unfortunately, these higher frequencies are much more susceptible to parasitic losses in signal strength caused by the signal transmission lines, connectors on the user's premise, devices connected to the signal transmission lines on the user's premise, etc. In the past many users have added relatively low-tech drop amplifiers on their premise to account for such losses. Because of the changes to increase the size of the upstream bandwidth, all of these drop amplifiers must be removed and or replaced. Additionally, because of the increased demands placed on the downstream content (e.g., high definition television, increased compression, etc.) the signal strength (i.e., level) of the downstream bandwidth must be maintained to closer tolerances than can typically be provided by the typical low-tech drop amplifier. Accordingly, as a result of increasing the size of the upstream bandwidth, the quality of the content moved to the higher frequencies within the downstream bandwidth may be significantly lessened causing a decrease in customer satisfaction and an increase in costly service calls.
In light of the forgoing, increasing the size of the upstream bandwidth: (i) may require a significant amount of capital expenditure in terms new filter devices and the manpower to install the devices; (ii) may not result in the expected large increases in upstream data throughput because of the interference signals injected from within each user's premise; (iii) may result in lower quality downstream content, and (iv) may inject additional interference signals that now fall within the additional upstream bandwidth, which would have otherwise been filtered out.